As a surface material of an absorbent article, such a material has been conventionally placed into market that has an embossed pattern for various purposes, such as suppression of wet feeling by decreasing the touch area with skin, and improvement in touch feeling associated with improved texture. Examples of the material include those disclosed in Patent Documents 1 to 5 below.
Patent Document 1 discloses an absorbent article using a surface sheet having a large number of ridges and grooves disposed alternately to avoid a flat area, in which the ridges are curved convexly, the grooves are curved concavely, and the grooves have a large number of openings disposed with intervals.
Patent Document 2 discloses a surface sheet having plural first ribs and plural second ribs, in which the first ribs are each formed with a top and both side walls continuing from both sides of the top and curving toward the backside of the surface sheet, have a cross section having a downward U shape, and extend lengthwise with being spaced respectively, the second ribs each have a top and are formed with being spaced respectively between the side walls of the first ribs, openings are formed with the first ribs and second ribs, and the tops of the second ribs have a lower height than the tops of the first ribs.
Patent Document 3 discloses such an absorbent article in that a large number of fusion lines containing a large number of fusion points dented from the surface sheet are formed, the fusion lines extend obliquely with respect to the lengthwise direction of the absorbent article to form concave grooves in a lattice pattern, and the plural fusion points are present at intersecting points of the fusion lines to form lattice points.
Patent Document 4 discloses a plastic sheet having a thermal plasticity and having a melt pattern (emboss pattern) applied to the sheet surface, in which the melt pattern is formed in such a manner that, in the condition where the plastic sheet is stretched, a virtual line connecting areas having no melt pattern in the substantially stretching direction is not linearly continued but is formed in a zigzag form or a rhombic pattern form, so as to form convex-concave shaped wrinkles corresponding to the arrangement of the melt pattern.
Patent Document 5 discloses an absorbent article using such a surface sheet that has a large number of elevated portions discontinuous in the lengthwise direction and the widthwise direction of the sheet, has a sheet thickness of from 0.5 to 10 mm under a pressure of 0.5 cN/cm2, and has a minimum distance between the adjacent elevated portions of from 0.5 to 15 mm, which is obtained in such a manner that after laminating fiber assemblies constituting first and second fiber layers, an emboss surface having a large number of pins disposed regularly (such as a peripheral surface of an emboss roll) is pressed onto the side of the first fiber layer to fuse the constitutional fibers of the first fiber layer and the second fiber layer at the positions pressed by the pins under heat.
Patent Document 1: JP-A-8-302555
Patent Document 2: JP-U-A-10-112
Patent Document 3: JP-A-7-328060
Patent Document 4: JP-A-2002-160293
Patent Document 5: JP-A-2003-126147